A gearwheel arrangement for a transmission of a vehicle, such as an electric vehicle, including: a shaft extending along a longitudinal axis of rotation, including an internal axial duct for guiding lubricant, a gearwheel including a base portion centered on the shaft and a plurality of gear teeth provided around a periphery of the gearwheel, the gearwheel preferably being configured for common rotation with the shaft. The gearwheel arrangement further includes an internal radial duct for guiding lubricant from the internal axial duct to the gear teeth. The internal radial duct may extend at least in part behind a gearwheel cover.

A power transmission device includes a pinion gear having a large pinion gear and a small pinion gear, a carrier that supports the pinion gear, a ring gear that engages with the small pinion gear, an oil supply unit positioned above a horizontal line that passes through a revolution center of the pinion gear, and a downstream side wall part facing a gear surface of the large pinion gear. The downstream side wall part is arranged to be adjacent to the oil supply unit further downstream in a revolution direction of the pinion gear than the oil supply unit when viewed from an axial direction.

A planetary gear system includes a sun gear, a plurality of planet gears connected to a carrier and engaging with the sun gear, and a ring gear assembly including a damper housing, and a ring gear connected to the damper housing and engaging with the plurality of planet gears. The ring gear includes a geared wall having a plurality of gear teeth engaging with the plurality of planet gears, and a damper housing attachment member radially spaced outward of the geared wall and attaching the ring gear to the damper housing. A first end of the geared wall and the damper housing engage each other via a plurality of squeeze film damping members, and a second end of the geared wall is connected to the damper housing attachment member via a flexible damping wall that is configured to provide a radial damping of the second end of the geared wall.

A differential gear accommodated in a differential case, includes: an axial cylinder having a cylindrical shape fitted onto a shaft; an annular wall having an annular shape protruding from an outer circumferential surface of the axial cylinder; a gear protruding from the annular wall on one side with respect to an axial direction of the shaft; a reinforcing rib protruding from an outer circumferential surface of the annular wall; and a first recess formed by boring the annular wall and opening the other side with respect to the axial direction of the shaft.

A gear assembly for an aeronautical engine that includes a first gear disposed at a centerline axis of the gear assembly; a second gear coupled to the first gear in adjacent radial arrangement to form a first mesh between the first gear and the second gear; a third gear coupled to the second gear in adjacent radial arrangement to form a second mesh between the second gear and the third gear; a collector rotatably coupled with the third gear; and a lubricant input portion disposed between a portion of the first gear and the second gear such that a first supply opening of the lubricant input portion is directed at the first mesh between the first gear and the second gear. The first supply opening provides a flow of lubricant to the first mesh with a portion of the flow of lubricant is collected by the collector.

A method of performing maintenance on an aircraft engine includes removing a propeller shaft of the aircraft engine to form an access volume at a center of the aircraft engine. The access volume extends axially and radially relative to a center axis of the aircraft engine. The method includes performing maintenance on a lubricant strainer positioned at a location of the access volume where a carrier of the aircraft engine engages an output of the aircraft engine.

A gearwheel arrangement for a transmission of a vehicle, such as an electric vehicle, including: a shaft extending along a longitudinal axis of rotation, including an internal axial duct for guiding lubricant, a gearwheel including a base portion centred on the shaft and a plurality of gear teeth provided around a periphery of the gearwheel, the gearwheel preferably being configured for common rotation with the shaft.

The gearwheel arrangement further includes an internal radial duct for guiding lubricant from the internal axial duct to the gear teeth. The internal radial duct may extend at least in part behind a gearwheel cover.

A gearwheel arrangement for a transmission of a vehicle, including: a gearwheel configured to be rotatable about an axis of rotation (A), the gearwheel including a gearwheel body and an annular gear tooth section extending around the gearwheel body, the gear tooth section including a plurality of external gear teeth, wherein at least a part of the gear tooth section extends past a radially outer portion of the gearwheel body in an axial direction (A) of the gearwheel, so that at least one radially inwardly facing surface is provided opposite of the external gear teeth, means for guiding cooling fluid toward the at least one radially inwardly facing surface so as to cool the gear tooth section during rotation of the gearwheel about the axis of rotation.

An epicyclic gear train includes a sun gear and planet gears mounted to a carrier and engaged to the sun gear. The planet gears and the carrier are rotatable about a center axis, and the carrier is engaged with a power output at a carrier-output engagement location. Ring gears are in meshed engagement with the planet gears. Planet gear bearings are disposed between one of the planet gears and the carrier. A lubrication interface is defined between each planet gear bearing and one of the planet gears. A bearing lubrication system includes a lubricant supply conduit extending between a conduit inlet at the carrier-output engagement location and conduit outlets at the lubrication interfaces of the planet gear bearings. A lubricant strainer is mounted about the conduit inlet at the carrier-output engagement location.

A planet carrier for a speed-reducing unit with an epicyclic gear train for a turbine engine, said planet carrier comprising a cage defining an internal space for assembling a central sun gear having an axis of rotation and an annular row of planet gears disposed around the axis and meshed with said sun gear, said cage comprising two substantially parallel annular walls centered on said axis and a cylindrical wall connecting said annular walls to their outer periphery, a first one of said annular walls being connected to a substantially cylindrical body, wherein a second one of said annular walls is formed as a single part with a lubrication grove, channel or duct.